The Knights of the Cross are pretty interesting in my opinion, but they also have a large problem as well. There are supposedly only three holy swords, two of which eventually fell into Dresden's hands and were never redistributed. First of all, WHY IN HELL would the church even allow Dresden to keep such relics? Wouldn't they want to take them and redistribute them immediately to worthy successors. There is no time for these swords to sit around idle, when there is a constant war to fight against evil.
Secondly, just THREE SWORDS in the entire world? Come on, there are numerous legends of TONS of other holy swords. What about the sword of Jenne D'arc for instance? She's a canonized saint who performed miracles on the battlefield, so don't tell me her blade wouldn't be a holy relic comparable to the swords that the Knights of the Cross wield.
Honestly, can only THREE SWORDS make a difference in the ENTIRE WORLD! Definitely shows the church doesn't care enough to fight evil if they depend on only three people to be their champions, while the regular priests just give their weak ass prayers and hope to make the world a better place. So SHOULD there be more than three holy swords in the Dresdenverse?